Apparatus for forming welding-portuberances on sheet metal and the lke.



, E'. KATZINGER Y APPARATUS POR FORMING WELDING PROTUBERANGBS 0N SHEET METAL AND THELIKE. APPLICATION FILED OT. 19, 1910. 'I 1,064,339, Patented June 10, 1913.

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UMTED STATES Parar ro EDWARD KTZINGER, OF CHICAGG, ILLINOIS. y

APPARATUS FOR FORMING WELDING-PROTUBERANCES ON SH v LIKE.

.Specification of Letters Patent. '.Ptnted June 10, 19H35.

Original application filed )Ia-y 9, i1919, 'Seria1 No. 560,102, Divided and i910. Serial Nn.587,812.

this'appnoation 'mee october 19,.

ving `Weldin -Protuberances on Sheet. Metal and the Li te, of which the' following is a specification.

This application is a division of my original application, Serial No. 560,102, iiled in the United States Patent OticeMay 9., 1910,

-and the present invention relates to an iniproved apparatus or mechanism for pre aring nietais for being united by spot wel ing, and it has for its primaryobject to provide an 'improved apparatus whereby a strip or piece of sheet metal may be stamped to provide welding protuberances thereon and when so stamped, the strip or sheet will be by said apparatus left in a perfectly flat condition.

Another object of the invention .is to provide an improved apparatus whereby the strip or sheet metal may be Aso stamped, while at the same timethe scale usually found on metal which has beenintroduced into a .pickling bath will be removed.

Other and further objects will appear 1n the specification and be more specificallyv pointed out in the 'appended claims, .reference bein@ had to the accompanying drawings whic illust-rate the strip or sheet metal in the different stages of its formation.l

In the drawings, Figure 'l is a view in elevation of cooperating dies by means of which a strip or sheet metal is provided 4with welding protuberances.l Fig. 2 is a similar view, illustrating the first stage of the process in preparing the strip of metal for spot welding, parts being shownl in section. Fig. 3 is a view .similar to Fig. 2 illustratin a further stage of the forma-tion Aof the strlp or sheet of metal. Fig, 4 is a view similar to Figs. 2 and showlngthe dies at the end of the stamtpmg operation.

Fig. 5 is a side elevation o the strip prolvided with a plurality of welding protuberances in the manner indicated in Figs. 2, 3 and 4. Fig. 6 is a top plan view of the strip shown in Fig. 5.

According to the present well known method of spot welding, one of the sheets may be provided with one or more protuberances which are pressed against the other sheet While a welding ,ourrent is be- EET METAL AND THE I,

ing passed' therethrough. These protuberf ences can be mosteasily and rapidly formed. between stamping dies but accordingto the present Well known m yliods the strip or 'sheet is bowed radiall in all directions around each irotuberanee so that the sheet has 'imparted shaped hollows. Moreover', or bar is thus stamped, the bends in saidbar thereto a plurality, et" lcup when the strip' corresponding to the lt'ieation 'of said hol-- lows cause the bar to assume an arcuate form. In consequence of these drawbacks,

it beooniesnecessary to hammer the sheet 'or strap out liat before .the `weldingtaire/s piace, an operation which consumes considerable time and effort. To provide stamp-l ing dies of improved construction and coni -formation whereby the hand straightening or flattening operation is rendered unnecessary, constitutes t'he'primar object oit this invention. By means of -tiie construction and Iarrangements of parts in lthel present-v device, however, a further beneficial result' accrues in that the oXid scales which are usually found on the metals to be welded are removed during the stamping oper-ation thus rendering uhnecessary the usual ling hath with its attendant expense and inconvenience. l

In pursuance of the objects'and purposes of the present invention, means are provided for clipping the metal4 oppositel to the cupping which occurs dining the ormation of the protuberance. For thisI purpose, stamping dies l and 2 are made use of, `the contiguously disposed ends of the shank portions 3 and 4 of which are .provided respegif-'Vly Witha protuberance 5 and recess 6 svlprdport-ioned and arranged asto form "15 a protuberance 10 on the metal to be stamped, when the dies are moved torreth r.V

position correspondingy to that-assumed by a bar after it has been operated upon by present well known types of stam ing dies.

The distinguishing'- eature of t e device forming the subject matter of the present invention resides 1n and is connected with the" l male Astamping operation being continued, however, until the .parts assume the positions shown in Fig. 4t, the bar 7 upon being removed from between the dies 1 and 2, as-A sumes the straight fiat position shown in F ig. 5, .inasmuch as the degree of' curvature iniparted to the end faces of the dies-1 and 2 is just siz'llicentV to overcome the cupping which takes place during the first part of the process. In Fig. 5 is indicated the final position `assumed by the bar 7 after it has been provided with a plurality of protuberances 10. As the process isy'carried outl and the'bar 7 passes by successive stages from the position shown in Fig. 2 to that shown in Fig.-

4, a complete rearrangement of the surface molecules takes place witlrthev result that the scales usually found on the surface of the bar, are entirely removed' thus insuring a' clean welding surface.

1. The combination with a' die provided' with a recess and a convex end face eiitendin around said recess, of a second die prol` V1 ed Wlth a projection adapted to coperate Wit-h the recess in the first said die to stamp a Welding protuberance in a piece of sheet metal, said second die being further lincasso provided with a cupped end -face. extending around said projection, the end faces of said dies being adapted to eoperatevto flatten the metal of said sheet around each protuberance after'it has been bent out of shape by the firstpart of the stamping operation.

2. The combination of cooperating dies, one having a projection with anannular beveled recess at the bottoni, and the other having a'depression with an edge concaved to correspond With'the said recess, the sai-d dies being efeetive to cup a metal in opposite directions by a single stamping operation. and to bend the metal 'whereby it will assume a dat osition when. released from the pressureoijthe dies. i

3. In an apparatus of the class described, the combination of a die formed with a pro` jection surrounded by a concavely arched recessI inclined toward the base ot' the pro- `ection anda co ieratincj die having a depression larger tian said projection and With an annular rim eonvexly arched to correspond with the said concavely arched recess of the other die whereby a piece ot' metal is bent irst4 in one direction and then in the other direction by the said arched portions during the formation oit" a Welding protuberance whereby the piece, when released by the dies, will be in a lat condition.

In testimony'whereof I have signed my name to this specification, in the presence of two subscribing Witnesses,` on this 17th day of October, A. D. :1910.

' EDWARD KATZINGER.

Witnesses: y j

C. I-I. SnnM, e FRANCIS A. HOPKINS.

Copies of this patent may 'n'e obtained for five. cents each, by addressing the Commissione;` of` Patents, Washington, D. C. 

